octy died ...burned valve & sparkplug ...pls help (long story)

[Meier]

Hi guys ...

I really hope someone has a clue about this...story is this

Octavia 1998, AKL 1.6 engine - 240.000 km ...

I was on winter holliday during cristmas it was very cold -30 degres celsious ...car sounded strange when started - but drove fine.... before trip i made sure oil was on top marking...

car did quite some Idle time because of the severe cold ..to get it defrosted ...

It was a trip on a total of 1200km when i came back home the oil warning lamp came on ..no oil left !!!!!!!! I was a bit worried where all that oil could have gone - did not notice smoke, no oil leaks ect ect I filled it up and went for a 50km drive

sudenly on accelerating up a hill I lost power....and took the car for a stop...it sounded like it was only going on 3 cylinders ..i thought of sparkplug/coil problems ...i humped the car back home ...

and got the plug out of cylinder 1 ..it looked like this :

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D#mn ...looked very odd I think...ok new set of new vw spec bosch plugs ...still no improvement ...

Since the car was booked for a Ditec treatment ..I had their mecanic look at it .... conclusion was it had burned a valve on cylinder 1...so ofcourse i wonder WHY ????

mecanic said they just do that sometimes...just unlucky i did spend around 1000£ for this ( not the ditec)

Got car back ..thought engine was a bit noise when idle but it drove ok...2 days after symtoms are same strang idle sounds like 3 cylinders again no power ...wow so got it back to the garage ...

they called me told me that it was just a faulty plug ( the ones in had only driven 3km they where new)....

So my question is .....

1 . WHAT IS GOING ON with the engine ... are things related ... I wonder ...did same thing happend from the beginning - BAD PLUG >>> driving the car >>> BURNED VALVE .....

2. and where on earth did all the oil go....could it have been all the long periods of idle and very cold climate and short runs during a week that made car use all that oil - (it normally uses a litlle oil)

I am very nervous that there are another thing wrong with the engine that causes the faulty plug ????

Pls any Ideas, clues ect ...im blank googling doest provide any things - cant even find a topic of a burned valve

Thx

[KenONeill]

You've burnt out 2 plugs and a valve on the same cylinder now?

I'm wondering if the relevant valve is sticking open? Possibly a sticky tappet?

The oil consumption could be related, because you'd have a higher than normal vacumn on the valve stem seal on that valve if so.

[rwbaldwin]

You've burnt out 2 plugs and a valve on the same cylinder now?

I'm wondering if the relevant valve is sticking open? Possibly a sticky tappet?

The oil consumption could be related, because you'd have a higher than normal vacumn on the valve stem seal on that valve if so.

+1

I assume it is an exhaust valve that is burnt. The engine will start to pump oil when the valve fails to seal. The valve will become red hot and will cause pre-ignition. My guess is that you don't smell petrol at the exhaust.

Did they check the valve guide?

Did they regrind the seat or just replace the valve? Regrinding the seat using a worn guide as the pilot is unlikely toseal well.

Did they check the tappet?

[Meier]

+1

I assume it is an exhaust valve that is burnt. The engine will start to pump oil when the valve fails to seal. The valve will become red hot and will cause pre-ignition. My guess is that you don't smell petrol at the exhaust.

Did they check the valve guide?

Did they regrind the seat or just replace the valve? Regrinding the seat using a worn guide as the pilot is unlikely toseal well.

Did they check the tappet?

I am to pick up the car today - they said that the mecanic could have dropped or somehow damaged the relevant plug ..im not sure if i buy that one ...also they said that the mechanic was not impress with how the engine was running !!!

but maby it was running ok - so asked me to come down and listen to the engine ....

I really hope this engine gets to run smooth and a lot extra kilometers ....I see in uk i can have a replacement engine with install for around 1000£ (in denmark 3000£)t ...somehow wish i had done that...but now i just cross

my fingers ...that there will be no more problems I will ask about the tappets and valve guides - and how the valve seat was grinded

[SILVER ROCKET]

they said that the mecanic could have dropped or somehow damaged the relevant plug ..im not sure if i buy that one ...also they said that the mechanic was not impress with how the engine was running !!!

but maby it was running ok - so asked me to come down and listen to the engine

Sorry, the `mechanic' is not sure if the engine is running properly and wants you to have a listen? Who's the expert, you or him? Get a new mechanic.

[Meier]

+1

I assume it is an exhaust valve that is burnt. The engine will start to pump oil when the valve fails to seal. The valve will become red hot and will cause pre-ignition. My guess is that you don't smell petrol at the exhaust.

Did they check the valve guide?

Did they regrind the seat or just replace the valve? Regrinding the seat using a worn guide as the pilot is unlikely toseal well.

Did they check the tappet?

Got the car back ..was actually driving ok ..BUT there is a significant smell of oil from the exhaust ..and it used 1l oil for aprox 100km ....not good ....

[KenONeill]

See posts #2 and #3 again! :(

[Meier]

See posts #2 and #3 again! :(

Mmm yeah - Im not quite sure what a sticky tappet is ?? would the mechanic not see this when he has the thing apart ...??

Are there any way to test for an open valve ....

Mechanic says compression is normal ....and he doesnt have a clue right now for the oil consumption ....

:-(

[KenONeill]

A tappet is the slack adjuster in the valve gear, between the camshaft and the valve stem (or the rocker if it was an overhead valve engine, but these are overhead camshaft engines). Basically, a sticky tappet will stop the its valve closing properly, leading to a lack of proper cooling of that valve head, and hence to verheating and melting of the valve. See http://en.wikipedia.org/wiki/4-stroke#Valvetrain and imagine that the exhaust valve doesn't shut fully.

The usual test for a sticky (or burnt) valve is a compression test. Ok, the mechanic says the compression is "normal", but I think there are 2 of us here who don't trust the mechanic. Can you get the actual figures from him? It's either right, or Fvcked Up Beyond All Recognition if all 4 figures are within 20PSI of each other. Without knowing what the figures actually are, we can't say which though.

[Meier]

A tappet is the slack adjuster in the valve gear, between the camshaft and the valve stem (or the rocker if it was an overhead valve engine, but these are overhead camshaft engines). Basically, a sticky tappet will stop the its valve closing properly, leading to a lack of proper cooling of that valve head, and hence to verheating and melting of the valve. See http://en.wikipedia.org/wiki/4-stroke#Valvetrain and imagine that the exhaust valve doesn't shut fully.

The usual test for a sticky (or burnt) valve is a compression test. Ok, the mechanic says the compression is "normal", but I think there are 2 of us here who don't trust the mechanic. Can you get the actual figures from him? It's either right, or Fvcked Up Beyond All Recognition if all 4 figures are within 20PSI of each other. Without knowing what the figures actually are, we can't say which though.

Ahh ok - well car went back to him this morning since it died on one cylinder again... this time another cylinder cylinder 2 - first time was cylinder 1 ...so after thinking they just called and said

that it possible was no way around a new engine ... and that they would not reccomend putting more money into this one !!!!! WTF ...I told them before they renewed the valves if they where sure that the burned valve

was not caused buy something else ...DAMN.... so now i spend 1000£ and 2L oil for driving 200km ...thats a bit sick

They propose a new ...used engine and replacement for 2000£ ..........I hate them :-)

[KenONeill]

Ahh ok - well car went back to him this morning since it died on one cylinder again... this time another cylinder cylinder 2 - first time was cylinder 1 ...so after thinking they just called and said

that it possible was no way around a new engine ... and that they would not reccomend putting more money into this one !!!!! WTF ...I told them before they renewed the valves if they where sure that the burned valve

was not caused buy something else ...DAMN.... so now i spend 1000£ and 2L oil for driving 200km ...thats a bit sick

They propose a new ...used engine and replacement for 2000£ ..........I hate them :-)

I see where they're coming from; it sounds to me like the engine's not been serviced properly, and the hydraulic tappets are all gunged up a bit. If you had the DIY skills to rebuild the head yourself, I'd suggest spinning the engine on the starter, with flushing oil in it, for as long as a battery will stand, recharge the battery and repeat. Now strip and rebuild the head, replacing all the tappets, drain the flush, and repeat the double spin treatment, then using a flushing oil as per recommendations.

Without those skills, an exchange motor might well be the best way to go.

[Meier]

I see where they're coming from; it sounds to me like the engine's not been serviced properly, and the hydraulic tappets are all gunged up a bit. If you had the DIY skills to rebuild the head yourself, I'd suggest spinning the engine on the starter, with flushing oil in it, for as long as a battery will stand, recharge the battery and repeat. Now strip and rebuild the head, replacing all the tappets, drain the flush, and repeat the double spin treatment, then using a flushing oil as per recommendations.

Without those skills, an exchange motor might well be the best way to go.

MMm its a bit strange the mechanic doesent know that it could be the tappets and that he did not check/clean or replaced them in the first place -

But can they really be the only reason it uses so much oil ...

Thanks for your continiously replies Ken ...it means a lot to get some qualified input in a case like this

[rwbaldwin]

Can you take it somewhere else? To a garage that has a proper mechanic!!!

Even if you need to get it towed, it is worth it to get someone who knows what they are doing.

[Meier]

Can you take it somewhere else? To a garage that has a proper mechanic!!!

Even if you need to get it towed, it is worth it to get someone who knows what they are doing.

Yes :-) Im getting it home today it can drive for a while maby only on 3 cylinders....

Right now im thinking about getting a "NOS" engine - its complete with clutch,flywheel ect ... and i got an offer by some skoda tec guy who will install it for me -

total cost engine 1300£ install 500£ ....sounds not to bad ...just hope i could get some money back from first mechanic....

But ehmm Ken did you think sticky tappets could cause an oil consuption around 1 Liter for 60miles ???

[rwbaldwin]

Yes :-) Im getting it home today it can drive for a while maby only on 3 cylinders....

Right now im thinking about getting a "NOS" engine - its complete with clutch,flywheel ect ... and i got an offer by some skoda tec guy who will install it for me -

total cost engine 1300£ install 500£ ....sounds not to bad ...just hope i could get some money back from first mechanic....

But ehmm Ken did you think sticky tappets could cause an oil consuption around 1 Liter for 60miles ???

It could be the valve seat, valve guide or the tappet. As soon as an exhaust valve sticks open/fails to seal, the valve will burn and the engine will start to pump oil.

The damage can occur very quickly.

It's good news that you have found a Skoda Tech to help you. He will be able to look at the valve/head and know exactly what to do.

[Meier]

It could be the valve seat, valve guide or the tappet. As soon as an exhaust valve sticks open/fails to seal, the valve will burn and the engine will start to pump oil.

The damage can occur very quickly.

It's good news that you have found a Skoda Tech to help you. He will be able to look at the valve/head and know exactly what to do.

..Ehmm yes ...but this is the guy who has the new engine for sale / he kept it as a spare for his own audi a3 ...so dont know if he is interested

in wrenching in da old engine ....:-)

[rwbaldwin]

..Ehmm yes ...but this is the guy who has the new engine for sale / he kept it as a spare for his own audi a3 ...so dont know if he is interested

in wrenching in da old engine ....:-)

Taking the cover off the old head will take 5 minutes. If you are in dispute with the first garage, it would be worth getting his opinion. I am not suggesting he try and fix the old engine.